Genetic generalized epilepsy (GGE) accounts for nearly one-third of all epilepsies. The feature of status epilepticus (SE) in patients with GGE has been rarely studied. We aimed to determine the electroclinical characteristics of SE in patients with GGE. In this retrospective study, nine patients with GGE were enrolled at Xijing Hospital, Xi'an, China from May 2014 to May 2020. SE was confirmed by 24-h video-EEG recording. The demography, clinical manifestation, brain MRI and SE pattern were analyzed. Of the nine patients in the study, seven were female. The mean age of the patients at the time of inclusion was 16.8 years (range 7-31 years), and the mean age at the onset of epilepsy was 10.9 years (range 6-17 years). The follow-up time ranged from 3 months to 6 years. Myoclonic absence status was identified in four patients showing eyelid myoclonia with absence and one patient showing perioral myoclonia with absences. Myoclonic SE was identified in three patients showing juvenile myoclonic epilepsy. Autonomic SE was found in one patient with eyelid myoclonia with absence. SE was terminated by oral midazolam in four patients. In the other five patients, SE terminated spontaneously. The seizure type of SE in patients with GGE is often consistent with their major symptoms. Oral midazolam may be an option to terminate SE in patients with GGE.

To investigate the electroclinical characteristics and the prognostic impact of generalized fast discharges in a large cohort of genetic generalized epilepsy (GGE) patients studied with 24-h prolonged ambulatory electroencephalography (paEEG). This retrospective multicenter cohort study included 202 GGE patients. The occurrence of generalized paroxysmal fast activity (GPFA) and generalized polyspike train (GPT) was reviewed. GGE patients were classified as having idiopathic generalized epilepsy (IGE) or another GGE syndrome (namely perioral myoclonia with absences, eyelid myoclonia with absences, epilepsy with myoclonic absences, generalized epilepsy with febrile seizures plus, or GGE without a specific epilepsy syndrome) according to recent classification proposals. GPFA/GPT was found in overall 25 (12.4%) patients, though it was significantly less frequent in IGE compared with other GGE syndromes (9.3 vs. 25%, p = 0.007). GPFA/GPT was found independently of seizure type experienced during history, the presence of mild intellectual disability/borderline intellectual functioning, or EEG features. At multivariable analysis, GPFA/GPT was significantly associated with drug resistance (p = 0.04) and with a higher number of antiseizure medications (ASMs) at the time of paEEG (p < 0.001) and at the last medical observation (p < 0.001). Similarly, GPFA/GPT, frequent/abundant generalized spike-wave discharges during sleep, and a higher number of seizure types during history were the only factors independently associated with a lower chance of achieving 2-year seizure remission at the last medical observation. Additionally, a greater number of GPFA/GPT discharges significantly discriminated between patients who achieved 2-year seizure remission at the last medical observation and those who did not (area under the curve = 0.77, 95% confidence interval 0.57-0.97, p = 0.02). We found that generalized fast discharges were more common than expected in GGE patients when considering the entire GGE spectrum. In addition, our study highlighted that GPFA/GPT could be found along the entire GGE continuum, though their occurrence was more common in less benign GGE syndromes. Finally, we confirmed that GPFA/GPT was associated with difficult-to-treat GGE, as evidenced by the multivariable analysis and the higher ASM load during history.

Perioral myoclonia with absences (POMA) is not recognized as a unique electro-clinical syndrome and studies suggest its inclusion under the genetic generalized epilepsy (GGE) spectrum. The aim of this study was to explore the prevalence and electro-clinical homogeneity of this disorder in an epilepsy monitoring unit. Between 2013 and 2019, among drug-resistant epilepsy patients who were referred for video-telemetry, those diagnosed with POMA based on the presence of documented absences with prominently observed peri-oral muscular contractions accompanied by generalized EEG features were included. Among 62 patients who were diagnosed with absence epilepsy, five finally met the criteria for POMA (8.1%) with late childhood or adolescent onset of epilepsy. Four (80%) had a referral diagnosis of focal epilepsy based on historical focal features with exacerbation of seizures on oxcarbazepine. All five patients demonstrated brief absences with orbicularis oris muscle contractions accompanied by subtle focal phenomenology. One patient had concurrent axial-appendicular myoclonic jerks precipitated by hyperventilation. While four patients had strikingly identical interictal and ictal characteristics of typical absence epilepsy, one patient demonstrated additional atypical generalized polyspike discharges without a "dart-dome" morphology. Therapeutic response to introduction of sodium valproate was noted in all five patients. Features that were not consistent with the diagnosis were apparent in one patient who was re-classified with combined focal and generalized epilepsy. Differentiating aspects in this patient included multifocal discharges, background slowing, fast-recruiting ictal rhythms and valproate resistance. This is one of the largest case series of POMA. This entity, which falls under the spectrum of GGE, remains under-diagnosed and its distinctive electro-clinical features need to be recorded in order to prevent misclassification as focal epilepsy of probable opercular origin. Background-slowing, atypical ictal rhythms and valproate unresponsiveness are not consistent with the diagnosis of this unique absence epilepsy. [Published with video sequences].

Some patients with genetic generalized epilepsy (GGE) may present with ambiguous and atypical findings and even focal brain abnormalities. Correct diagnosis may therefore be difficult. We retrospectively collected six patients investigated on the epilepsy monitoring unit with MRI abnormalities mimicking focal cortical dysplasia (FCD-like) or heterotopias, but with semiology and EEG features of GGE. We compared them to four additional patients with GGE and nonmigratory abnormalities. All six patients presented with frontal MRI lesions: radial ("transmantle," n = 4), cortical-subcortical (n = 1), and periventricular heterotopia (n = 1). Five had positive family histories. Semiologic lateralizing signs compatible with the lesion were seen in four. Five patients had 3/s spike-wave complexes, with an asymmetric appearance in three. Regional EEG changes matched with the side of the abnormality in three patients. Invasive EEG (n = 2) or postoperative outcomes (n = 3) argued against an ictogenic role of the MRI abnormalities. Histology showed mild malformation of cortical development, but no focal cortical dysplasia. The six patients were finally diagnosed with juvenile myoclonic epilepsy (n = 2), juvenile absence epilepsy (n = 2), or GGE not further specified (nfs, n = 2). Compared to these patients, the other four (final diagnoses: childhood absence epilepsy, n = 1; perioral myoclonia with absences, n = 1; and GGE nfs, n = 2) had no lateralizing EEG findings. Patients with GGE may have coincidental MRI abnormalities. These cases are challenging as frontal epilepsy and GGE can present with similar semiologies. GGE with coincidental FCD-like lesions/heterotopias is in particular difficult to diagnose as patients have more lateralizing features (in semiology and EEG) than those with tumors. A detailed noninvasive presurgical evaluation may be justified. We point out red flags that may help to distinguish GGE from frontal epilepsy, even in the presence of brain abnormalities: 3/s spike waves (even if asymmetric), changing lateralizing signs at different times, and a positive family history hinting at GGE.

The rare syndrome of perioral myoclonia with absences (POMA) is described as a specific type of idiopathic generalized epilepsy in which absence seizures are accompanied by prominent perioral myoclonus as a consistent symptom. We present a 52-year-old man who was referred to our department due to treatment-resistant epilepsy. Typical seizures were described as rhythmic twitching of the lips which started at six years old, and his first convulsive seizure occurred at around 20 years old. Based on video-EEG recordings, we present two distinct EEG patterns accompanied by slight differences in clinical manifestations, which appear to be atypical of POMA. Firstly, consciousness was preserved during seizures, with no manifestation of absences. Secondly, regarding the EEG features, in some of the seizures, the perioral motor symptoms were tonic rather than myoclonic. The defining features of POMA are discussed in relation to this case.